This paper examines in detail some modifications to main rotor aerodynamic modeling that will affect the off-axis response of a helicopter. Three different approaches are examined: a version of momentum theory extended to include wake distortion, a first-order aerodynamic lag model, and an aerodynamic phase correction. it is shown that all three approaches result in similar changes to the off-axis response when applied to a simplified linear model of the coupled pitch-roll dynamics in hover. Numerical values for the inflow parameters are determined using system identification and are compared to theoretical predictions and previously identified values. Comparisons are also made between a nonlinear simulation model incorporating the extended momentum theory and flight test data for a UH-60 in hover, demonstrating considerable improvement in the off-axis response prediction.
The effect of inflow models on the predicted response of helicopters
Journal of the American Helicopter Society ; 43 , 1 ; 25-36
1998
12 Seiten, 15 Bilder, 2 Tabellen, 14 Quellen
Aufsatz (Zeitschrift)
Englisch
The Effect of Inflow Models on the Predicted Response of Helicopters
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|TIBKAT | 1987
|Helicopters and aeroplane-helicopters
Engineering Index Backfile | 1921
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